Powered Two Wheelers Research Articles

Usage of e-Scooters in Urban Environments

Abstract Since the introduction of the internal combustion engine (ICE), modern mobility has fundamentally changed. Today, it is impossible to imagine modern transportation without motorized vehicles. Powered Two-Wheelers (PTWs) represent a relevant section of such vehicles. In recent years, electric low-powered PTWs, also called e-scooters, became a notable trend. Without excessive emissions and noise, as well as convenient dimensions, e-scooters can help European cities ease their increasing problems with traffic, emissions, and parking. In this paper, we present the results of a real-life field test, performed in the City of Munich, Germany. By providing six vehicles, 38 subjects were able to incorporate an e-scooter into their everyday lives. Recorded with travel diaries and a pre-post-survey, usage and attitudes were evaluated. Results show that a majority of daily trips is suitable for e-scooters and charging infrastructure is sufficient for this kind of vehicle, while subjective safety, weather conditions, and baggage capacity are restricting attributes.

Design of an after-market lower limb protector for scooters: preliminary estimation of effectiveness

The number of vehicles on the roads is constantly increasing. Considering the circulating park in Italy, recent data show that Powered Two-Wheelers (PTWs) have increased by about 20% just in ten years (2006-2016). PTW crashes are not decreasing at the desired pace and thus rider safety is still a concern. Previous studies showed that lower limbs are the region of the body with the highest probability of injury in a road crash. The aim of this paper is to perform a preliminary assessment of the effectiveness for a new concept of leg protector. The device is conceived for after-market installation on scooters and it is designed to mitigate leg injuries reported by the riders in side impacts at low speeds. To assess the effectiveness of the protector, five crash tests configurations of the scooter equipped with the protector were reproduced in a virtual environment. A Hybrid III model was selected as the best dummy compromise for the analysis to calculate the safety performance. Being the dummy not validated for side impacts, the evaluation was performed through a comparative analysis with and without the protector. Two different series of simulations were performed: moving-stationary (with stationary motorcycle) and moving-moving. The results of the first set of analyses (moving-stationary) show that the protector has provided a protection to the lower limbs in each configuration. In addition, the injuries to the upper body (head and chest) are equivalent or show a slight decrease. Analyzing the kinematic of the impact, the protector has a restraining effect on the rider. In the moving-moving analyses, the protector does not provide a significant improvement in leg protection, and the injury parameters worsen compared to the reference configuration. The study contributes to solve the problem of motorcyclists lower limbs protection in road crashes, studied on several occasions in the past without a concrete solution.

Factors associated with adolescent active travel: A perceptive and mobility culture approach – Insights from Ho Chi Minh City, Vietnam

Sustainable transport modes, such as walking and cycling, have great benefits but the uptake is decreasing in Vietnam due to motorisation. Individual perceptions of travel and wider mobility cultures are increasingly seen as an important aspect in shaping travel patterns, in particular active travel. The understanding of this in youth active travel in Vietnam is not clear. The aim of this study is to understand how social factors and the physical environment influence adolescent active travel in Ho Chi Minh City (HCMC). A survey in HCMC targeting adolescents aged 11–16 (n = 525) across nine districts around the city centre was conducted. We adapted a comprehensive conceptual framework of active travel behaviour in the context of data availability and the study area. We also included variables pertaining weather, traffic safety, street vendors and road accident experiences, which are more relevant in powered two-wheeler (PTW) traffic saturated, tropical cities in a South East Asian setting. The results show positive association between favourable built environments (obstruction free pathways, food attractions and tree cover), social interactions (peer groups, parents and neighbourhoods) and negative association with traffic, air pollution and prior accident experiences. The findings highlight the importance of considering the interrelations of variables, whilst also identifying future research directions. Policy makers in HCMC, or in similar cities, should consider developing intervention strategies to improve the attractiveness of active travel.

Examining Injury Severity of Moped and Motorcycle Occupants with Real-Time Traffic and Weather Data

AbstractCurrently studies exploring the effect of real-time traffic and weather characteristics on crash severity are relatively limited, and studies focusing on powered two-wheelers (PTWs) are eve...

Safety ranking definition for infrastructures with high PTW flow

Abstract Powered two-wheelers (PTWs) provide a suitable mode for a large portion of population in many cities due to rider's personal convenience and the vehicle supposed easiness of manoeuvring. At the same time PTWs present serious safety issues compared to other motorized vehicles. This paper reports the main outcome of study carried out in Rome, where this mode is very popular and assesses the economic efforts to make infrastructure safer for PTWs. The methodology, extensively described in the paper, includes three steps: the accident analysis, the development of economic indicators of accidents costs, the maintenance priority. In the first step the location of the PTWs local accidents are identified, then the accidents are analyzed by means of the suitable indicators and, among these the safety potential (SAPO). Lastly, according to the results of the analyzed indicators the need of infrastructure maintenance will be defined. Usually SAPO is applied to rural areas, but here it has been adapted to describe the phenomena of the urban area in hand. As a result, the estimation of the saving potential to improve the infrastructure safety levels, thus reducing the amount of accidents, is presented, along with recommendations on how to upscale the SAPO at city level.

A headway to improve PTW rider safety within the EU through three types of ITS

IntroductionThe current safety situation for Powered Two Wheelers (PTW) within the EU is alarming. According to EU statistics, PTW riders account for 17% of all fatal road injuries in the region and twice as many fatalities per hundred thousand registered vehicles compared with occupants of cars. In recent years, too little attention has been given to Vulnerable Road Users (VRUs), including PTW users, in the development of Intelligent Transport Systems (ITS). Therefore, ITS should be developed that consider PTW riders an integral part of traffic; we focus on three systems that we believe have the potential to improve safety among PTW riders, namely Intersection Safety (INS), the Powered Two Wheeler oncoming vehicle information system (PTW2V), and the Vulnerable road user Beacon System (VBS). The present study aims to estimate quantitatively the safety impacts of the selected ITS for PTW riders in the EU-28, once the systems are fully adopted and meet selected future scenarios for 2020 and 2030.MethodAn ex-ante method suggested by Kulmala (Accident Analysis and Prevention 42:1359–1369, 2010) was further developed and applied to assess the safety impacts of ITS specifically designed for VRUs. As suggested by the method, the analysis started by determining the impact mechanisms through which the selected ITS systems affect the safety of PTW riders.ResultsAccording to the main results, all the systems we studied have a positive impact on PTW rider safety by preventing fatalities and injuries. The greatest effects, based on 2012 accident data and full penetration, could be attained by implementing PTW2V (283 fewer yearly fatalities) and INS (261 fewer yearly fatalities). The weakest effect was found with VBS (216 fewer yearly fatalities). Forecasts for 2030, also based on estimated accident trends and penetration rates, confirm an expected edge for INS and PTW2V in terms of safety.

Crash sequence based risk matrix for motorcycle crashes

Considerable research has been conducted related to motorcycle and other powered-two-wheeler (PTW) crashes; however, it always has been controversial among practitioners concerning with types of crashes should be first targeted and how to prioritize resources for the implementation of mitigating actions. Therefore, there is a need to identify types of motorcycle crashes that constitute the greatest safety risk to riders - most frequent and most severe crashes. This pilot study seeks exhibit the efficacy of a new approach for prioritizing PTW crash causation sequences as they relate to injury severity to better inform the application of mitigating countermeasures. To accomplish this, the present study constructed a crash sequence-based risk matrix to identify most frequent and most severe motorcycle crashes in an attempt to better connect causes and countermeasures of PTW crashes. Although the frequency of each crash sequence can be computed from crash data, a crash severity model is needed to compare the levels of crash severity among different crash sequences, while controlling for other factors that also have effects on crash severity such drivers’ age, use of helmet, etc. The construction of risk matrix based on crash sequences involve two tasks: formulation of crash sequence and the estimation of a mixed-effects (ME) model to adjust the levels of severities for each crash sequence to account for other crash contributing factors that would have an effect on the maximum level of crash severity in a crash. Three data elements from the National Automotive Sampling System - General Estimating System (NASS-GES) data were utilized to form a crash sequence: critical event, crash types, and sequence of events. A mixed-effects model was constructed to model the severity levels for each crash sequence while accounting for the effects of those crash contributing factors on crash severity. A total of 8039 crashes involving 8208 motorcycles occurred during 2011 and 2013 were included in this study, weighted to represent 338,655 motorcyclists involved in traffic crashes in three years (2011–2013)(NHTSA, 2013). The top five most frequent and severe types of crash sequences were identified, accounting for 23 percent of all the motorcycle crashes included in the study, and they are (1) run-off-road crashes on the right, and hitting roadside objects, (2) cross-median crashes, and rollover, (3) left-turn oncoming crashes, and head-on, (4) crossing over (passing through) or turning into opposite direction at intersections, and (5) side-impacted. In addition to crash sequences, several other factors were also identified to have effects on crash severity: use of helmet, presence of horizontal curves, alcohol consumption, road surface condition, roadway functional class, and nighttime condition.

Evaluating the safety impacts of powered two wheelers on a shared roadway in China using automated video analysis

ABSTRACTThe last decade witnessed a rapid growth in the number of powered two wheelers (PTWs) on Chinese roads. PTWs offer a convenient, flexible, and affordable mobility solution. They are also considered as an environment-friendly alternative to automobiles. Despite these advantages, concerns have been raised about the safety impacts of PTWs on China's urban roadways. The main objective of this study is to evaluate the safety impacts of PTWs on a shared roadway in Kunming, China, using automated computer video analysis. The study pursues the following tasks: (1) to perform a comprehensive safety analysis based on the automated traffic conflict techniques, (2) to analyze the nonconforming (NC) travel behaviors of PTWs, (3) to examine the relationship between the detected traffic conflicts and the PTWs travel behaviors, and (4) to study the steering action of PTWs by estimating their movement yaw rate. The automated analysis revealed several findings regarding the PTWs travel behaviors on the shared roadway. The results showed that a considerable number of conflicts with high severity were caused by PTWs on the shared roadway. It was observed that PTWs are likely to engage in NC behaviors while traveling on the shared roadway. Also, more than one half of the NC behavior events resulted in PTW conflicts. On the other hand, the yaw rate analysis showed that not every PTW took swerving maneuvers when involved in a conflict situation. The findings in the article identify the hazardous travel behavior associated with PTWs. Such behavior can have negative safety consequences on roadways shared with more vulnerable road users such as cyclists.

Identifying Predictable Patterns in the Unconventional Overtaking Decisions of PTW for Cooperative ITS

In the modern challenging urban environment, powered two wheelers (PTW) are selected for their everyday commuting. The way motorcycles and scooters travel through traffic is systematically emphasized in the recent relevant literature as being complex, especially in relation to overtaking. In this paper, meta-optimized Decision Trees, a special case of machine learning (ML) models, are developed in order to model the unconventional overtaking patterns of PTW drivers. Based on detailed naturalistic trajectory data collected using video footage from unmanned aerial vehicles (UAV) in a three-lane arterial in Athens, Greece, two different models of PTW driving behavior are developed. The first model addresses the decision of the PTW driver to overtake or not the preceding vehicle. The second model focuses on PTW driver's intention to overtake or undertake (pass from the right) it. The developed decision tree models are further analyzed in relation to the revealed significant factors during overtaking. Following, the applicability of the developed algorithms in the context of intelligent transportation systems and connected vehicles is discussed, which reveals the importance of acquiring quality data using advanced equipment combined with advanced ML approaches for advanced modeling methods.

Modeling and analysis of mixed flow of cars and powered two wheelers

In modern cities, a rapid increase of motorcycles and other types of Powered Two-Wheelers (PTWs) is observed as an answer to long commuting in traffic jams and complex urban navigation. Such increasing penetration rate of PTWs creates mixed traffic flow conditions with unique characteristics that are not well understood at present. Our objective is to develop an analytical traffic flow model that reflects the mutual impacts of PTWs and Cars. Unlike cars, PTWs filter between cars, have unique dynamics, and do not respect lane discipline, therefore requiring a different modeling approach than traditional “Passenger Car Equivalent” or “Follow the Leader”. Instead, this work follows an approach that models the flow of PTWs similarly to a fluid in a porous medium, where PTWs “percolate” between cars depending on the gap between them.Our contributions are as follows: (I) a characterization of the distribution of the spacing between vehicles by the densities of PTWs and cars; (II) a definition of the equilibrium speed of each class as a function of the densities of PTWs and cars; (III) a mathematical analysis of the model’s properties (IV) an impact analysis of the gradual penetration of PTWs on cars and on heterogeneous traffic flow characteristics.The proposed model could contribute as an enabler for ‘PTW-aware’ future Cooperative Intelligent Transport Systems technologies and traffic regulations.

Belted Safety Jacket: a new concept in Powered Two-Wheeler passive safety

Powered Two Wheelers (PTWs) offer a viable solution to reduce traffic congestion and promote personal mobility. However, vehicle characteristics and conspicuity issues lead to an overrepresentation of PTWs in accident statistics. This work presents an innovative approach for concept design of new passive safety devices and their development. The landscape of possible design solutions was examined with an in-depth analysis of the state of the art and with the use of conceptual design tools. Candidate solutions underwent a feasibility assessment and they were crossed-checked with the rider needs, identified via a specific on-line survey. The concept of a new passive safety device was born: a Belted Safety Jacket (BSJ). An initial assessment of the device effectiveness for the reduction of riders’ injuries was performed by comparison of the main biomechanical indexes (HIC, Nijmax, Chest Deflection and Viscous Criterion) in a relevant accident configuration, reproduced in a virtual environment, with and without the device. Later a full factorial Design of Experiment (DOE) was carried out to understand the influence of the device geometrical variables (i.e. possible design parameters) on the biomechanical indexes. The results demonstrated that the integration of BSJ onto the vehicle has the potential to significantly reduce the occurrence of serious injuries during a PTW accident versus a car, since it prevents the contact of the rider with the opponent vehicle. The analysis of the accident kinematic with BSJ suggests that the device will be beneficial also in accidents with other vehicle types.

Role of sensation seeking and attitudes as mediators between age of driver and risky driving of Powered Two Wheelers

IntroductionThis study examines the effect of age of driver on risky driving of Powered Two-Wheelers (PTW) employing sensation seeking and safety attitudes as mediators. MethodsA survey was conducted with 1299 PTW drivers (1089 males and 210 females) within the age of 18 and 63years, living in the state of Kerala, India. The questionnaire consisted of 31 items to measure sensation seeking, safety attitude, and risky driving of the drivers. ResultsMediation models were examined using sensation seeking as mediator and secondly safety attitudes as mediators. The relationship between the driver's age and risky driving was fully mediated by all the three variables. Practical applicationsResults of this study suggest that safety strategies should be employed to reduce risky driving tendencies that could be achieved by shaping or adapting the mediators (reducing sensation seeking and enhancing safety attitudes). This goal could be reached by starting to educate children about this at an early stage when they are at school as well as by social learning and safety awareness campaigns.

Modeling the effect of traffic regimes on safety of urban arterials: The case study of Athens

Abstract This study aims to divide traffic into meaningful clusters (regimes) and to investigate their impact on accident likelihood and accident severity. Furthermore, the likelihood of powered-two-wheelers (PTWs) involvement in an accident is examined. To achieve the aims of the study, traffic and accident data during the period 2006–2011 from two major arterials in Athens were collected and processed. Firstly, a finite mixture cluster analysis was implemented to classify traffic into clusters. Afterwards, discriminant analysis was carried out in order to correctly assign new cases to the existing regimes by using a training and a testing set. Lastly, Bayesian logistic regression models were developed to investigate the impact of traffic regimes on accident likelihood and severity. The findings of this study suggest that urban traffic can be divided into different regimes by using average traffic occupancy and its standard deviation, measured by nearby upstream and downstream loop detectors. The results revealed potential hazardous traffic conditions, which are discussed in the paper. In general, high occupancy values increase accident likelihood, but tend to lead slight accidents, while PTWs are more likely to be involved in an accident, when traffic occupancy is high. Transitions from high to low occupancy also increase accident likelihood.

Integration of vulnerable road users in cooperative ITS systems

IntroductionThis paper describes the development of an architecture for the integration of Vulnerable Road Users (VRUs), i.e. pedestrians, cyclists and powered two-wheelers (PTWs) in Cooperative ITS (C-ITS) systems, and the requirements for VRU devices.MethodsThis paper starts with a literature overview on research related to safety applications using communication between vehicle and VRU, and an analysis of the different use cases for C-ITS for VRUs. An architecture is developed, starting from an architecture of C-ITS systems and incorporating the different alternative configuration for VRUs. Starting from the architecture and the use cases, the requirements for VRU devices are defined. Finally, a roadmap regarding C-ITS applications for VRUs is developed.ResultsC-ITS technologies allow to communicate with low latency in highly dynamic environments. C-ITS will be integrated in vehicles and can also become available for VRUs, either as an application on a smartphone or as a dedicated device, which can be integrated in the VRU’s vehicle. Two levels of use cases can be identified: awareness of the presence of VRUs near potentially dangerous situations, and collision risk warning, based on trajectories of the road users. A roadmap was developed aligned with the roadmap of the automotive industry.ConclusionsAwareness related use cases are relatively close to the market, as they do not put stringent requirements to the (localization) sensors at infrastructure or vehicles. For the collision risk warning use case, the technical requirements for VRU devices towards sensor accuracy and calculation capabilities are challenging. Other challenges are power consumption, context sensitivity, channel congestion, privacy and security of messages. Standardisation of the messages exchanged between VRUs and other road users and infrastructure is a key issue.

A methodology for the evaluation of road accidents health care costs for powered two-wheelers: The Rome case study

Road safety is a central issue in many political agendas virtually worldwide, scientific literature on road accidents prevention abounds as the consequent awareness of the higher vulnerability of Powered Two-Wheelers (PTWs). Not the same can be said about the assessment of the economic side of the problem: decision-makers seem to underestimate the relevance of public health care costs to recover and rehabilitate those involved in road accidents, especially riders. The paper, thus, deals with a specific approach to assess the current methods to estimate health care costs due to road accidents, with the goal to have a special focus on the problems arising when the PTWs are involved. The motivation for such approach is due to the unsuitability of these current methods, which underestimate the health care costs. Therefore, the paper reviews some references for health care costs, which often are parts of the calculation of the overall road safety social costs. Although the effectiveness of these methods is undisputable, more specific criteria and indicators are required to have health care costs properly assessed, especially about PTWs, since no univocal cost items are considered; consequently health care expenditures markedly vary. The paper, then, analyzes the road accidents occurred in Rome, Italy, from 2010 to 2012, as a case in point of this problem, defines the health care costs occurred and revises results taking as leading criteria the level of vulnerability of the involved PTWs victims and the severity of the event, in order to provide more accurate estimations of such costs.

Influence of demographics on risky driving behaviour among powered two wheeler riders in Kerala, India

This study is designed to explore the statistical significance of the demographic variables with respect to six risky driving behaviour variables, i.e., drunken drive (DD), helmet usage (HU), cell phone usage (CU), family involvement (FI), commitment to safety (CS) and negligence of vehicle examination (NE), which influence risky driving behaviour of Powered Two Wheeler (PTW) riders. A questionnaire survey is conducted among the PTW riders from all districts of Kerala State. The results show that, male riders are significantly more involved in drunken driving and cell phone usage, while female riders are significantly more inclined to helmet usage and family involvement. The age of the rider shows significant difference on cell phone usage. The educational level of the rider exhibit significant difference on all six variables. The riders educated up to degree and above degree level are found to be more inclined to helmet usage, while drunken driving, cell phone usage and negligence of vehicle examination are found appreciably low among them compared to riders educated up to Grade 10 and Grade 12. Results of this study can be used to conduct appraisal and counselling programme about the unsafe and risky driving acts, resulting from drunken drive, helmet non usage, cell phone usage while driving and negligence of PTW examination among the male and young riders educated up to 12 Grade.

Contributing factors to motorcycle injury crashes in Victoria, Australia

IntroductionThe increased popularity of powered two wheelers (PTWs) in Australia, combined with their vulnerability in the event of a crash, necessitates new strategies to prevent serious injury crashes. The purpose of this study was to use case-series data collected from a recent motorcycle case-control study to analyse contributing factors to crashes using a safe systems approach. MethodsA total of 235 injured riders were recruited and completed a questionnaire-based interview, each followed by a detailed inspection of the case motorcycle and crash site by a trained crash investigator. Primary and secondary contributors to the crash were judged based on all available information sources. Analysis of the most frequent contributing factors included separation of cases into single and multi-vehicle crashes. A stepwise logistic regression was used to test for factors associated with human error for multi-vehicle crashes. ResultsTwo thirds of crashes investigated involved another vehicle or road user(s). For multi-vehicle crashes the most common crash scenario involved another vehicle failing to give way to the rider, and the primary contributor was a perception failure or traffic scan error on the part of the other road user. A number of secondary factors were found to be significantly associated with human error type (other road user or rider error), including rider age, traffic density, inappropriate speed of the PTW, and a road design issue. For single vehicle crashes, the most common primary contributor was a misjudgement or control error on the part of the rider, with inappropriate speed as the most frequent secondary contributor. ConclusionsDespite the complexity of factors involved in PTW crashes resulting in injury, a number of significant associations exist between road users as the primary contributing factor (rider or other road user) and secondary factors, including rider age, traffic density, speed and road design issues.

Leather for motorcyclist garments: Multi-test based material model fitting in terms of Ogden parameters

This paper is focused on experimental testing and modeling of genuine leather used for a motorcycle personal protective equipment. Simulations of powered two wheelers (PTW) accidents are usually performed using human body models (HBM) for the injury assessment equipped only with the helmet model. However, the kinematics of the PTW rider during a real accident is disturbed by the stiffness of his suit, which is normally not taken into account during the reconstruction or simulation of the accident scenario. The material model proposed in this paper can be used in numerical simulations of crash scenarios that include the effect of motorcyclist rider garment. The fitting procedure was conducted on 2 sets of samples: 5 uniaxial samples and 5 biaxial samples. The experimental characteristics were used to obtain the set of 25 constitutive material models in terms of Ogden parameters.

Virtual hybrid human body model for PTW safety assessment

Road traffic accidents cause one of the highest numbers of severe injuries. The numbers of deaths and seriously injured citizens prove that traffic accidents and their consequences are still a serious problem to be solved. Virtual human body models play an important role to assess injuries during impact loading especially for scenarios, where complex dynamical loading is taken into account. The most suffering group is so called vulnerable road users (VRU) like powered two-wheelers (PTW) riders. The presented work contributes to increasing safety of PTW riders by implementing virtual human body model for injury risk analysis. The scalable hybrid virtual human body model Virthuman, which was formerly developed, validated and demonstrated in impact scenarios, is improved by updated neck and shoulder models in order to describe the realistic kinematics during complex long duration impact loading and presented in the oblique impact scenario compared to the THUMS results.

Powered two-wheeler riders' risk of crashes associated with filtering on urban roads

ABSTRACTObjective: The objective of this study is to estimate the crash risk per kilometer traveled by powered two-wheeler (PTW) riders filtering through traffic on urban roads.Methods: Using the traffic injury crashes recorded by the police over a period of 3 years on 14 sections of urban roads in the city of Marseille, France, and a campaign of observations of PTWs, the crash risk per kilometer traveled by PTWs filtering was estimated and compared to the risk of PTWs that did not filter.Results: The results show that the risk of PTW riders being involved in injury crashes while filtering is significantly higher than the risk for riders who do not filter. For the 14 sections studied, it is 3.94 times greater (95% confidence interval [CI], 2.63, 5.89). This excess risk occurred for all PTW categories. Furthermore, no space appears to be safer than the others for filtering. Riders filtering forward along the axis of the carriageway, along bus lanes, or between traffic lanes (lane-splitting) all have a crash risk greater than the risk of those who do not filter.Conclusions: All measures limiting the practice of filtering by PTWs on urban roads would probably contribute to improving the safety of their users.